For those of you following this thread I attach the first of four responses I received from the Live OneCare support people. Microsoft have been very responsive and following their instructions has eliminated the problem. The current status is that I'm still working thru the System Configuration Utility, restoring services one at a time to pin down what actually caused the problem, and will let you know the result.
"Thank you for contacting Windows Live OneCare Support. My name is Jenny, and I will be working with Bruce to assist you with this issue.
From the problem description, I understand that after Windows Live OneCare is installed, it takes a long time to open a Word, Excel document, or open a link in Outlook. You have tried to run virus and registry scan, many problems in registry information cannot be fixed. If I have misunderstood, please feel free to let me know.
I understand the inconvenience you have experienced. Please be assured that I will do my best to help you.
Let's disable all startup items and third party services when booting. This method will help us determine if this issue is caused by a loading program or service on computer startup. Please perform the following steps:
Clean Boot
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1. Click "Start", go to "Run", and type "msconfig" (without quotation marks) in the open box then click OK to start the System Configuration Utility.
2. Click the "Services" tab, check the "Hide All Microsoft Services" box and click Disable All (if it is not gray).
3. Re-enable the checkboxes for "OneCare Firewall" and "OneCare AntiSpyware and Antivirus" service.
4. Click the "Startup" tab and take note of the items that are checked and the items that are unchecked, as we will want to return your computer to this configuration when we finish troubleshooting. Once the checked items have been noted, click Disable all. After that, find and re-check the checkbox in front of "winssnotify.exe".
5. Click OK.
Then, restart your computer.
Note: Temporarily disabling the Startup Group only prevents the startup programs from loading at startup. This should not affect the system or other programs. We may still manually run these programs later.
Please check if the issue persists. If it persists, we will try other solutions to troubleshoot the issue. However, if the issue disappears, I will help you to narrow down the cause of the issue. Therefore, please let me know the result after disabling all startup items and third party services. After sending the result, please return to Normal Mode via the following steps:
1. Click "Start" and choose "Run", type "MSCONFIG" (without quotation marks) and press ENTER.
2. Click on the "Startup" Tab and return your computer to the configuration we noted in the previous step. Place a checkmark in the items that were previously checked which will return your computer to its initial configuration.
3. Click on the "Service" Tab and repeat the above steps. Then, click "OK" and click Restart when you are prompted to restart your computer.
Meanwhile, please help to collect the following information for further research:
Support Log
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1. Open Windows Explorer and browse to this folder if Windows is installed on C::
C:\Program Files\Microsoft Windows OneCare Live\
2. In this folder, double click the file named OneCareSupport or OneCareSupport.exe.
3. When it finishes the information collection, note the path and file name of the information file. (Generally, it is C:\OneCareSupportData.zip)
4. Please send this file to v-30jeli@mssupport.microsoft.com
System Information
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1. Press Start, Run and type in msinfo32. Press OK.
2. Choose Save from the File menu and save it as an NFO file.
3. Find the file, right-click on this file, click "Send To", and click "Compressed (zipped) Folder".
4. Please send it to v-30jeli@mssupport.microsoft.com.
Please try my suggestions and let me know the results at your earliest convenience. If anything is unclear, please feel free to let me know. I will follow up with you as soon as possible.
I look forward to your reply."
In a follow-up memo the Live OneCare supoport people told me the system information file I sent them showed that vestiges of two anti-virus/firewall aps I had previously removed (AVG and AD-Aware) were still on the system so I also removed them.
Again, I have to thank the Live OneCare people for being so responsive to my request for assistance.